in their mobile home in southern virginia. this was a crime of conspiracy and lewis herself didn't fire the shots. the two men who did, including lead trigger man, matthew schallenburger only got life sentences. the judge called teresa lewis the head of the serpent. her attorneys say her iq is in low 70s, in the level of retardation. >> is it your basic contention she was manipulated into this crime? >> yes, schallenburger has stated and experts who examined her agree, she was being used by him, not the other way around. >> he had an affair with teresa lewis before the killings. her attorneys cite a prison letter from schallen dullesbubu. he later committed suicide in prison. prosecutor david grimes says this. >> i can frankly say teresa lewis is as evil a person as i've ever met. >> reporter: grimes says his investigation showed lewis herself took an active role in the plot, that she admifed and manipulated everyone from her late husband, to her lover, to her children. tests his side conducted contradict those that say she's